Spring hook



FIG. 1 is a perspective view of a spring hook showing my new design;

FIG. 2 is a front elevation view, the rear view being a mirror image thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a left side view thereof;

FIG. 5 is a top plan view thereof; and,

FIG. 6 is a bottom plan view thereof. 

CLAIM The ornamental design for a spring hook, as shown and described. 